1. Field of the Invention
This invention relates to an image formation apparatus connected to a network.
2. Description of the Background Art
In recent years, image formation apparatuses, such as a printer, a facsimile, a copying machine and a composite machine, have been connected to plural terminals on a network and image formation jobs are transmitted to respective image formation apparatuses from the terminals. Usually, in an image formation apparatus, image formation jobs are executed according to an order of reception of the jobs. Of image formation jobs, there are jobs that are wanted to be executed taking precedence over the other jobs, while there are jobs to be executed in no particular hurry. Therefore, a case arises where, priorities are assigned to respective jobs, such that the priorities are reflected on an order of execution of image formation job.
Various kinds of image formation apparatuses have been proposed, examples of which include an image formation apparatus in which priorities of jobs are determined based on elapsed times from time points when respective image data are inputted (for example, see Japanese Patent Laid-open Publication No. 2002-137500), an image formation apparatus in which a job with a shorter processing time for printing predicted from a past record or the like has a priority in print processing (for example, see Japanese Patent Laid-open Publication No. H06-168085) and an image formation apparatus in which image formation of an image data with a higher priority assigned in advance according to a level of emergency is processed at an earlier time point (for example, see Japanese Patent Laid-open Publication No. H08-163332).
As for conventional image formation apparatuses, for example the image formation apparatuses described in the above patent literatures, in an apparatus, a priority of a job is assigned based on a input time point of image data and; in another apparatus, a job with a shorter processing time is subjected to print processing with a higher priority, each of which is useful for improvement on a print efficiency. Moreover, in a still another conventional image formation apparatus, priorities corresponding to levels of emergency are given to respective image data and a job with a higher priority is executed at an earlier time point. In such image formation apparatuses, priorities are assigned to jobs in an order of execution thereof and a priority change on jobs can be individually performed. In printers connected to a network as done in recent years, however, even in a case where, of many jobs, a series of plural jobs concerning image data related to one another are desired to be collectively outputted, a priority change has to be done in execution of each of the series of plural jobs, having led to great inconvenience.
Image data received in a conventional image formation apparatus is rasterized and enters a state of print-waiting. Therefore, a priority change is limited to a job or jobs in a state of print-waiting and there is a restraint that the priority change is performed only at a specific timing.